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Early visual deprivation is known to have profound consequences on the subsequent development of spatial visual processing. However, its impact on temporal processing is not well characterized. We have examined spatial and temporal contrast sensitivity functions following treatment for early and extended bilateral visual deprivation in fifteen children born with congenital cataracts in rural India. The results reveal a marked difference in post-treatment spatial and temporal sensitivities. Whereas spatial processing in newly sighted children is significantly impaired relative to age-matched controls, temporal processing exhibits remarkable resilience and is comparable to that in the control group. This difference in spatial and temporal outcomes is especially surprising given our computational analyses of video sequences which indicate a strong linkage between the spatial and temporal spectral content of natural visual inputs. We consider possible explanations for this discrepancy. [ABSTRACT FROM AUTHOR]

The long-standing nativist vs. empiricist debate asks a foundational question in epistemology – does our knowledge arise through experience or is it available innately? Studies that probe the sensitivity of newborns and patients recovering from congenital blindness are central in informing this dialogue. One of the most robust sensitivities our visual system possesses is to 'biological motion' – the movement patterns of humans and other vertebrates. Various biological motion perception skills (such as distinguishing between movement of human and non-human animals, or between upright and inverted human movement) become evident within the first months of life. The mechanisms of acquiring these capabilities, and specifically the contribution of visual experience to their development, are still under debate. We had the opportunity to directly examine the role of visual experience in biological motion perception, by testing what level of sensitivity is present immediately upon onset of sight following years of congenital visual deprivation. Two congenitally blind patients who underwent sight-restorative cataract-removal surgery late in life (at the ages of 7 and 20 years) were tested before and after sight restoration. The patients were shown displays of walking humans, pigeons, and cats, and asked to describe what they saw. Visual recognition of movement patterns emerged immediately upon eye-opening following surgery, when the patients spontaneously began to identify human, but not animal, biological motion. This recognition ability was evident contemporaneously for upright and inverted human displays. These findings suggest that visual recognition of human motion patterns may not critically depend on visual experience , as it was evident upon first exposure to un-obstructed sight in patients with very limited prior visual exposure, and furthermore, was not limited to the typical (upright) orientation of humans in real-life settings. [Display omitted] • Congenitally blind patients after sight restoration spontaneously identified human, but not animal, point light walkers. • Visual recognition was evident upon first exposure to un-obstructed sight despite very limited prior visual exposure. • Recognition ability was not limited to the typical (upright) orientation of humans in real-life settings. • Recognition of human locomotion patterns may not depend on extensive prior visual exposure. [ABSTRACT FROM AUTHOR]

Abstract: A novel analogue CMOS design of a cortical cell, that computes weighted sum of inputs, is presented. The cell’s feedback regime exploits the adaptation dynamics of floating gate FET ‘synapse’ to perform competitive learning amongst input weights as time-staggered winner take all. A learning rate parameter regulates adaptation time and a bias enforces resource limitation by restricting the number of input branches and winners in a competition. When learning ends, the cell’s response favours one input pattern over others to exhibit feature selectivity. Embedded in a 2-D RC grid, these feature selective cells are capable of performing a symmetry breaking pattern formation, observed in some reaction–diffusion models of cortical feature map formation, e.g. ocular dominance. Close similarity with biological networks in terms of adaptability and long term memory indicates that the cell’s design is ideally suited for analogue VLSI implementation of Self-Organizing Feature Map (SOFM) models of cortical feature maps. [Copyright &y& Elsevier]

Abstract: We report the growth and characterization of group III-nitride semiconductor layers on graphene grown by chemical vapour deposition. GaN, AlGaN alloys, and InN layers are grown using an AlN nucleation and a buffer layer. We investigate the effect of varying growth temperature and V/III ratio and show that under optimized growth conditions preferentially semipolar oriented nitride layers can be obtained. These layers, though polycrystalline, are highly oriented and show strong room temperature photoluminescence, thus showing graphene to be a novel substrate for the growth of III-nitride materials. [Copyright &y& Elsevier]

Abstract: An efficient synthesis of ophiocerins A and C has been achieved via a common intermediate. The stereogenic centers were generated by means of Jacobsen’s hydrolytic kinetic resolution and Sharpless kinetic resolution. [Copyright &y& Elsevier]

Abstract: An efficient enantioselective convergent approach for the synthesis of (−)-pinellic acid 1, α- and β-dimorphecolic acid (2 and 3) from 1,9-nonane diol is described. The synthetic strategy features Sharpless asymmetric hydroxylation, Sonogashira coupling and Birch reduction. [Copyright &y& Elsevier]

Abstract: An enantioselective synthesis of herbarumin III is described employing Jacobsen’s hydrolytic kinetic resolution and Sharpless asymmetric dihydroxylation as the key steps. [Copyright &y& Elsevier]

Anxiety is a neurological disorder that is characterized by excessive, persistent, and unreasonable worry about everyday things like family, work, money, and relationships. The current therapy used for the treatment has many disadvantages like higher cost, severe adverse reactions, and has suboptimal efficiency. There is a need to look for more innovative approaches for the treatment of anxiety disorder which overcomes the disadvantages of conventional treatment. Recent findings suggest a strong correlation of glutamate with anxiety. Some promising drugs which have a novel mechanism for anxiolytic action are currently under clinical development for generalized anxiety disorder, social anxiety disorder, panic disorder, obsessive-compulsive disorder, or post-traumatic stress disorder. Similarly, an interrelation of oxytocin with neuropeptide S or glutamate or vasopressin can also be considered for further evaluation for the development of new drugs for anxiety treatment. Anxiolytic drug development is a multi-target approach, with the idea of more efficiently equilibrating perturbed circuits. This review focuses on targeting unconventional targets like the glutamate system, voltage-gated ion channels, and neuropeptides system either alone or in combination for the treatment of anxiety disorder. [ABSTRACT FROM AUTHOR]

Abstract: An efficient total synthesis of decarestrictine J has been achieved using ring-closing metathesis and Yamaguchi esterification as key steps. The stereogenic centres were generated by means of iterative hydrolytic kinetic resolution (HKR) of racemic epoxides. [Copyright &y& Elsevier]

Abstract: The first total synthesis of aspinolide A has been achieved using ring-closing metathesis as a key step. The stereogenic centers were generated by means of hydrolytic kinetic resolution (HKR) of racemic epoxides. [Copyright &y& Elsevier]

Abstract: A short and practical enantioselective synthesis of tarchonanthuslactone has been achieved in high diastereomeric excess using iterative Jacobsen’s hydrolytic kinetic resolution and ring closing metathesis as the key steps. [Copyright &y& Elsevier]

Abstract: An efficient enantio- and stereocontrolled total synthesis of (+)-boronolide from valeraldehyde is described. The key steps include a Sharpless asymmetric dihydroxylation, a chelation controlled Grignard reaction followed by Sharpless asymmetric epoxidation and a ring closing metathesis. [Copyright &y& Elsevier]

An efficient enantioselective synthesis of (R)- and (S)-massoialactone has been achieved. The key steps are the hydrolytic kinetic resolution of a racemic epoxyheptane with (R,R)-(salen)–CoIIIOAc complex and ring-closing metathesis of homoallylic alcohol derived acrylate esters using Grubb’s catalyst. [Copyright &y& Elsevier]

An asymmetric synthesis of (S)-oxybutynin 1 is described using the Sharpless asymmetric dihydroxylation of α-cyclohexylstyrene as the key step. [Copyright &y& Elsevier]

Abstract: An efficient synthesis of lactone moiety of compactin has been achieved. The stereogenic centers were generated by means of iterative proline-catalyzed sequential α-aminoxylation and Horner–Wadsworth–Emmons (HWE) olefination of aldehydes. [ABSTRACT FROM AUTHOR]